For parents worried about children in their 20s who hop from job to short-term job, switch romantic partners with the seasons, alter educational paths and “boomerang” back home — spoiler alert! By the time they’re 30, the kids will, for the most part, be all right.

They’ll likely be settling into careers and steady relationships, exhibiting hallmarks of what previous generations considered responsible adulthood.

The exploration and ambivalence common among 18- to 29-year-olds are par for the course for what Clark University psychology professor Jeffrey Jensen Arnett calls “emerging adults.”

Arnett will be discussing and signing the book, which just hit the shelves, at 10 a.m. Saturday at Tatnuck Bookseller, 18 Lyman St., Westboro.

“It’s very much a research-based guide to parents of kids in this life stage,” Arnett said in an interview at his Worcester home.

He said that while he has been researching this previously little-known life stage for 20 years, he felt it would be presumptuous to write a parents’ guide when he didn’t have emerging adults of his own. His twins aren’t quite there yet – they’re 13 years old — but he found an ideal writing partner in Fishel, who has two sons in their 20s.

The book culls data from the Clark University Poll of Emerging Adults, a national survey of more than 1,000 young people ages 18 to 29, as well as an Internet survey of some 500 parents of emerging adults and interviews with 90 parents.

“I realized I was seeing a new life stage. Now as we all know, 30 is the new 20,” Arnett said. “It’s very much up in the air. They’re undecided and that can be very difficult for parents.”

Arnett divides emerging adulthood into three general stages: launching, roughly ages 18 to 22; exploring, ages 22 to 26; and landing, ages 26 to 29. With each stage, emerging adults gain a little more self-knowledge, skills and, hopefully, resources to step out on their own.

But it’s a much longer process than what today’s baby boomer parents went through, when they became adults as soon as they left home for college or immediately thereafter, got a job, got married and had children.

Arnett said: “Emerging adulthood is a high time for parental anxiety because this is when it really matters, in terms of finding a stable job and meaningful love partner. Parents often have a timetable of expectations from their own youth that their kids aren’t following. Parents should relax because times have changed.”

The challenge for parents, he said, is stepping back while staying connected, a recurring theme throughout the book.

“You can’t control their lives the way you used to. They have to choose their own life. It has to be their own struggle,” he said.

Falling back on parental support, such as moving home so emerging adults can get on their feet financially while gaining work or educational experience, isn’t the sign of failure that it once might have been. It can provide a useful boost, if parents can afford it. But expectations should be clear between parents and children about financial or other household contribution, time limits and a plan for moving on.

Arnett said that support for finishing a college degree was particularly important, since research shows that graduates have half the unemployment rate of young people without degrees.

“It’s misguided to say no support. Their chances of success go down,” he said.

Arnett said that advice applied as well to letting emerging adults pursue their own academic or career interests, rather than pressuring them to go into a high-paying field they hate and may soon abandon.

“What you don’t want is for your kid to have three expensive years of school and drop out because they hate it, left with piles of debt and no benefits,” he said.

There are times, however, when parents should intervene. Just as when they were preschoolers and safety issues were non-negotiable, when emerging adults show signs of mental or physical illness, or struggle with disabilities, parents need to play a stronger role.

So how can a parent tell when Junior’s lethargic sitting around the house all day is a symptom of difficulty finding a job in a tough economy and when it’s a sign of depression? Or when does regularly going out for drinks with friends turn into alcohol or drug addiction?

The authors provide specific checklists for diagnoses of serious conditions that should be red flags for getting professional help, including depression, bipolar disease, schizophrenia, eating disorders and addiction.

While emerging adults follow their own developmental path, Arnett and Fishel discuss the parallel journey experienced by midlife parents, now in their 40s and 50s.

With active childrearing duties over and 30 or 40 years of life ahead, parents may have the freedom to pursue new work or outside interests. Couples have time to rekindle their own relationship — or perhaps come to grips with problems that were swept under the rug when children were around. Like their children, they’re (re)defining themselves for the next chapter.

Arnett’s message is largely reassuring for both parents and their emerging adults.

“Yes, it takes longer to grow up than it used to, but not because they’re lazy, selfish or stupid,” he said. “They’re idealistic; they strive hard to make it in a tough world; they’re very tolerant in a diverse world. The fact that they grow up later ... means we should support them and give them the tools that they need to make it successfully to adulthood.”

Contact Susan Spencer at susan.spencer@telegram.com. Follow her on Twitter @SusanSpencerTG.

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